Statuskoodin

Statuskoodin (Finnish for "status code") refers to a numeric or alphanumeric indicator that communicates the outcome or state of an operation within a system. Statuskoodin is used across computer networks, software applications, and information systems to enable automated handling, logging, and user feedback. In practice, a component returns a status code along with optional human-readable text; the consumer uses the code to decide next steps.

In web technologies, HTTP status codes are the most widely recognized example. They are three-digit values grouped into categories: 1xx informational, 2xx success, 3xx redirection, 4xx client error, 5xx server error. Examples include 200 OK, 201 Created, 204 No Content, 301 Moved Permanently, 400 Bad Request, 404 Not Found, and 500 Internal Server Error. Some APIs also include more specific codes and messages.

Outside HTTP, status codes appear in databases, operating systems, and network protocols. They serve similar purposes: indicating success, failure, or special conditions so software can handle responses programmatically, retry failed operations, or trigger error reporting and telemetry. In many systems, status codes are standardized by specifications or vendors, while some environments define custom codes.

Design considerations for status codes include determinism, granularity, and backward compatibility. Well-designed codes enable clear error handling, improve automation, and reduce ambiguity in cross-system communication. See also: HTTP status code, error handling, status message.